Art of forming castings.



No. 698,593. -Patemd Apr..2s, |902.

c. H. YEEDER,

ABT 0F FBMNG CASTINGS.

` (Applicgtion filed Hay 21. 1900.

(No Model.) 2Sh`eets-Sheet L M" "if fitness es 4 [nvenor:

Veede;

Tn: cams Pneus on, PnoTaumm wAsHmcoN. uv c.

No. 698,593. Patented Apr. 29, |902.

c. H'. vEEma'. ARJoFFoRMmGcASTmGS.

(Application med my 21. 1900. (No Model.) 2 SheetsfSheet "2.

TN: Nonms PETERS co. PHaYcm'mo., wAsHmsoN. D. c.

A NTTED STATES PATENT EEICE.

CURTIs H. vEEDER, on HARTFORD, CONNECTICUT.

ART OF FORMING CASTINGS.

SEECIFICATION forming part 0f Letters Patent No. 698,593, dated April 29, 1902.

Application tiled May 21, 1900,

T0 all whom, tammy concern.-

Beit known that I, CURTIS I-I. VEEDER, a citizen of the United States, residing in Hartford, in the county of Hartford and State of Connecticut, have invented certain new and useful Improvements in the Art of Forming Castings, of which the following is a specilication.

This invention relates to improvements in the art of forming castings; and it has for its main object the formation of dense homogeneous castings having faces so perfectly formed that the castings will not need to be subjected to the usual operations of planing, turning, dac., but can be used with the bearing-surfaces in the condition in which they come from the mold and under conditions where exceptionally Well-liuished bearingsurfaces are required in order to permit the proper movements ofV parts upon one another and can be assembled with other parts even Where the most minute projections of a complex casting have to be accurately fitted into correspondingly-minute indentations of a coacting part.

It is Well known that in the ordinary methods of formin g castings the latter when formed have a more or less open structure, the intermolecular spaces being filled with small bubbles of air and other gases or metallic vapors, while blow-holes of considerable size, are of frequent occurrence. These objec` tionable results have been avoided somewhat by casting metal under pressure in molds that have not been exhausted or by pouring the metal into an open mold located in an exhausted chamber. The former of these methods results in a product more dense and somewhat more homogeneous than when the casting operation iscarried out in the ordinary manner-that is, without applying pressure to the molten metal-but the air is still entangled in the molten metal and does not al- Ways escape before solidification of the latter begins, and as a result blow-holes are of common occurrence even in castings which are formed under pressure. When the metal is merely poured into a mold located in a vacuum-chamber','of course there are no blow- 5o holes in the casting; but the metal is not condensed and compacted, because it has not Serial No. 17,331. (No model.)

been subjected to compression, and, moreover, unless it is the metal will not fill the mold thoroughly and will not reproduce perfectly the fine lines, projections, and indentations of an intricate pattern.

I have found that by producing a vacuum in the mold into which the metal is to be poured and then forcing the molten metal under pressure into the exhausted mold until the latter is completely filled the casting will be free from blow-holes and from bubbles of air and thermochemically-generated gases and metallic vapors and that the metal will be forced into all the spaces and corners of the mold, no matter how small they may be, so as to fill the same completely and form a casting corresponding in contour to the mold, every minute projection orindentation in which will be reproduced perfectly as an indentation or projection in the finished casting, no matter how complex the pattern to be reproduced may be. Moreover, the compressing action exerted upon the metal in the exhausted mold will result in compacting and condensing the metal most thoroughly and in forming a casting having a dense and homogeneous molecular structure throughout and presenting when fractured a finely-crystalline appearance.

The molten metal may be delivered to the mold in many Ways, provided that great pressure is exerted against the walls of the mold at the instant the latter is filled; but I prefer to inject the metal after it has been set in motion in substantially the same way that a body of fluid is set in motion in an ordi-nary hydraulic ram, and when this is `done a body of molten metal will be injected into the mold at such a high velocity that when the mold is filled the sudden stoppage of thejflow at the moment of complete iilling will result in the exertion upon the walls of an exhausted mold of a pressure so great that the metal will be forced into every portion of the mold and will be so throughly compressed, even in the nest spaces and Vcorners of the mold, that the resultingprojectionsfand corners of the casting will be as perfectly condensed as the body portion thereof and the condensation of the metal will be so complete that the casting will not withdraw fromthe Walls of the IOO mold in solidifying, and hence there will be substantially no shrinkage for which to make allowance.

In order that the structure of a casting may be very finely crystalline, it is desirable to cool the molten metal as rapidly as it is possible to do so without weakening the resultant casting, and when the crystallization of the metal is checked by hastening the solidification thereof the tendency of the molten metal to form large crystals in cooling will be avoided. It is especially desirable to accomplish this result when the metal employed to form the casting is one which tends to crystallize quickly and form large crystals, as is the case, for example, with the metal antimony, which is one of the metals that will be used most frequently in forming castings by means of my improved process. When this metal especially is present, it is desirable to hasten the crystallization or else large crystals will form and the resultant product will not be perfectly homogeneous throughout.

Another feature of my process which I deem of importance is the subjection of the molten metal to additional compression after the metal has been forcibly injected into the mold and has filled the latter, the principal object of this additional step in the process being to compress the metal into a smaller space, and thus form a casting more condensed and having more metal within a given space than a casting which has not been subjected to this additional compressing action.

All of the various operations hereinbefore described and certain modifications thereof which will hereinafter be referred to, being in their nature elemental actions, maybe performed without the aid of mechanism; but as it is desirable in practice to carry out each sequence of operations with the utmost precision I prefer to employ mechanism for more readily performing the several steps of the operation, and hence I have shown a mechanism suitable for this purpose, this mechanism being illustrated in the drawings accompanying this specification and forming 'part of the present application,and in Which- Figure 1 is a sectional side elevation of a casting-machine suit-able for the purpose of practicing my improved process. Fig. 2 is anenlarged sectional detail illustrating the manner in which the metal is subjected to final compression after it has been forced into the mold; and Figs. 3 to 8, inclusive, are details illustrating certain cam movements, Which will be hereinafter more particularly described. v g

Similar characters designate like parts in all the figures of the drawings.

In practicing my improved process there are many ways of exerting pressure upon the molten metal and upon the walls of the mold at the moment of complete filling and also many ways of exhausting a mold into which molten metal is to be delivered. I have found that all of the line channels and sharp corners of a mold may be most perfectly lled when molten metal is forced thereinto in a solid column under high velocity and an eX- ceedingly high pressure developed and immediately exerted directly against the Walls of the mold. Ordinarily the metal will be set in motion before communication withV the mold is established, and after said metal has begun to move under the inliuence of its own velocity, which may be developed in any suitable way, pressure will be applied to increase the force with which the metal will beinjected into the mold, and at the proper time, which may be at the moment when the molten metal is moving with maximum velocity, communication with the mold may be established and every other outlet-opening closed practically simultaneously in order to prevent any loss of pressure.

For the purpose of injecting metal into a mold, such as O, in the manner just described I may make use of a melting-pot, such as M, having a well 6, communicating, by means of a passage 7 with a valve-chamber, such as 8, in which will be placed a valve, such as o, so constructed and operating in such a manner as to control two openings, such as lO and 8', respectively, at different points in the valvechamber. Normally this valve will close the passage l0, and at such time of course the passage 8 will be open and molten metal may flow from the main portion of the meltingpot into the valve-chamber; but these openings should be so located with respect to each other and to the cut-olf faces of the valve that the passage lO may be opened and that at 8 closed practically simultaneously by a very slight movement of the valve. The valve @may be either freely movable within the valve-chamber to close the passage 8' when pressure is exerted on the valve by the molten metal or else it may be held positively in the position shown in Fig. l by some suitable part, such as the rock-arm 35', after there has been developed in the chamber 8 a pressure sufcient to shift the valve to close said passage 8. Ordinarily pressure will be exerted upon the walls of the valve-chamber and upon the valve v, located therein, through the passage rand the well G, in Which latter a plunger, such as p, may work and may be operatedin any suitable manner. When this plunger is forced down, the metal in the well b', the passage 7, and the valve-chamber S will of course receive and transmit the pressure of the plunger, and as the passage -S is the only one then open a portion of the body of metal in said valve-chamber will seek an outlet through said passage S'. Hence the pressure of the plunger will set up a circulation of the metal through the well 6, tbe passage 7, the valve-chamber 8, and the opening S' into the main body of metal in the meltingpot, and thus kinetic energy or @is oiled. of the molten metal will be developed. As the velocity of the circulating metal increases, the kinetic energy thereof, and hence the pressure ICO IIO

exert-ed upon the walls of the valve-chamber and upon the valve o located therein, Will also increase. If the valve o be mounted so as to be freely movable at this time to close the opening 8', ksaidvalve will be shifted to the left, as seen in Fig. l, as soon as the pressure in the valve-chamber is sufficient to overcome the inertia of the valve, the hydrostatic pressure of the main body of metal on the left hand end of the valve, and the suctionY at the righthand end of said valve if the mold be in its proper position at this time andis being or has been exhausted, as should be the case. These three forces tending to hold the valve o in `position to keep the passage 10 closed will be sufficient to prevent the closureof the passage 8 for an appreciable period of time, and duringthis period the metal will begin to circulate in the manner just described; `but if no means other thanl these forces be utilized to hold the valvein its closed position the pressure in the valve` chamber will be sufficient to open the valve before the moving body of metal will have developed its maximum kineticenergy under the influence of the pressure thatmay be exerted by the plungerlp. Henceif the valve be operated in this manner it Willopen very soon after the plunger begins to descend.`

Now the force Withwhih the molten metal is injected into the mold is dependent upon several factors, one of the most important of which is the velocitydeveloped by the metal before the passage 8 is closed. If the maxi` mum velocity of this column of metal be developed, it will be evident that the energy exhibited by the stream which enters the mold Will be Very much greater than is the casewheuonly a portion of such velocity is developed. Hence when it is desired to ex-A ert the maximum pressure uponthe Walls of themold at the moment of complete filling of the same in order to force the metal most y the plungerp may be continued for a longer f I /f period of time than isrequired to develop Within the chamber 8 a pressure sufticient'to overcome the inertia of the valve, the `hydrostatic pressure, and the suction of the exhausted mold-space. When the descent of the plunger is continnedfor the proper period of time,`themaximum velocity ofthe molten metalwill be developed, inthe construction shown, and also the maximum ratio of the pressure uponthe Walls'of the valve-chamber to the pressure upon the walls of the opening 8', owing to the fact that as the metal is set ing due to the gradually-decreasing resistance1 opposed by the mass offmetal inthe body of the melting-pot to the efflux of metal through the opening 8 after the" inertia of that por# tion of the mass adjacent tdsaidopening-has .stant ratio is reached and a maximum constant velocity of ow through 8. If this descent of the plunger be continued until the pressure in the valvefchamber and the velocity ofthe stream flowing through 8 are very much greater than are required to shift the valve and close the passage S', itwill be evident that this increase -in the force-that serves to shift the valve will Aloe due chieiiy to the increased velocity of the circulating metal as comparedwith the velocity of the same When the valve is shifted at `the moment that the pressure in the valve-"chamber becomes sufficient to accomplish'this result.

Whether the velocity developed in the molten metal be just sufficient orbe very much greater than is 'necessary to shift the valve the valve when shifted should move rapidly in order that the whole force of the moving body of metal may be transferred instanta-l neously from the opening 8 to the opening l0 without appreciable loss and exerted upon the body of metalin the valve-chamber to project a solid column of metal violentlyinto the mold body ofmetal entering the mold is thus pro- A1cm O and into every corner thereof; The Whole jected with tremendous forceagainst asolid 1 the metal developed before theshifting ofthe valve and' theA additional or continuedfpressure of the plunger p are both exerted" upon the moving column ofmetal to carry and force" the same forward into the mold the' resultant great'final pressure exertediuponthe Walls *of 1 the mold at the moment the mold completely fills and the owstopswillldrive or ram the metal into every cornerfof the mold and also condense-the metal, and this final great pressure `is only exerted against the Walls of the mold `\vhen"there is no' air or gas present to cushionthe blow and prevent the sudden stoppage of the iioW.` It should be understood`,howeverythatit willnothbe necessary infall cases to develop the maximum" velocity of the metal inthe Well 6, the

f and -immovable body, and as thevelocity of uIIO quickly in order that it may not retard" the` Y j ust been described and which consists in forc-l ing the metal under pressure into the moldA is an important one; but if it were the only one relied upon the castings resulting from that operation alone would in nearly all cases be imperfect, for the reason that they would contain more or less occluded air and generated gases and metallic vapors in the intermolecular spaces and in the pockets or blow-holes of the completed casting. The exertion of pressure upon the molten metal to force the latter into the mold is not, however, the only means relied upon to form close-grained and perfect castings, for in nearly every case it will be found necessary to produce a vacuum within the mold in order to obtain the best results, and this is done in the present case. Hence if the molten metal be forced in the proper manner into an exhausted mold as there will be little or no air in the mold-space there will be little or none occluded by themetal of the casting. In order to produce the most perfect results, however, I deem it desirable to do something more than exhaust the mold, as the molten metal injected into the mold will almost always contain some air occluded thereby and more or less thermochemically-generated gases and metallic vapors, and these should all beeliminated from the metal in the mold-space before the casting cools. Obviously if the mold be merely exhausted and no vent be provided for the escape of these generated gases and vapors the latter will remain in the casting after the cooling of the latter, and the finished casting will be more open in structure and less homogeneous than when formed entirely of molten metal from which all other bodies have been removed. These gases and vapors can be removed most perfectly by applying suction to that body of metal which on cooling forms the finished casting, and in order to accomplish such removal not only will the metal be forced into the mold at one point in the mold-space and suction maintained at another point therein during the filling of the mold, but this suction should be maintained substantially.

constant throughout the filling of the mold in order that all of the foreign elements-viz., the residual atmosphere of the mold-space,the air which is occluded by the molten metal, the gases generated in the latter, and the metallic vapors-may be drawn from the molten metal, preferably into an evacuated space in which the suction is maintained substantially constant in order that the high degree of vacuum produced in the mold-space and in the evacuated space into which the atmosphere of the mold is exhausted may be maintained and the reduction of the degree of vacuum which would occur if the air, generated gases, and metallic vapors accumulated, owing to the removal of the suction, prevented. Of course the suction so produced and maintained at a different point in the mold-space from that at which the molten metal enters serves by re 'ducing the resistance opposed to the column of metal injected into the mold to facilitate the entrance of the metal into every corner 0f the mold, and the effective pressure on the metal entering the mold-space is greater than it would be if any material resistance, even that of a highly-attenuated residual atmosphere such as that described, were opposed' to such pressure.

In the present case I have shown a simple form of mold, such as O, having two moldsections, such as o and o', eachof which may comprise two or more parts. In this case the mold-sections fit tightly together and are mounted on a carrier, such as II, in such a manner that the mold may be moved up and down in front of the discharge-opening 10 and also toward and from the latter and yet be held closed and pressed firmly against the faceof the discharge-nozzle l2, as by means of a key or wedge, such as 2Q, when a casting is to be formed. In this case the carrier I-I is mounted so as to move up and down in a vertical guide, such as 25; and has a horizontal guide 26', in which the mold-sections are supported for horizontal movement. The mold-space will preferably be formed in a pair of plates or dies, such as 18 and 19, fitted tightly in the mold-sections o and o', but removable therefrom. The mold-space formed between these sections when the mold is closed willpreferably communicate, by means of fine channels, such as shown herein, with means for exhausting the mold-space, and these passages should of course be small enough to enable their Walls to chill the metal before it flows very far, and thus prevent clogging of the connections through which the mold-space is exhausted. Here jointed tubes or pipes, such as 30, connected in such a manner as to permit the necessary vertical and horizontal movements of the mold, communicate With a pair of air-pumps, such as P and P. These pumps have a pair of valves, such as 86 and 86', controlling communication between the mold-space and the pumpcylinders. In this construction the port of the valve 86 communicates directly with the piping 30, while that of the valve 86' may communicate with such piping through another tube, as 3l. Y

The pump P should be so operated as to withdraw substantially all of the air from the mold-space before the passage 10 is opened to deliver metal into the mold, and the valve 86 should shut off communication between the cylinder of the pump P and -the moldspace before communication is made with the cylinder of the pump P. It will be evident that when the mold-space is exhausted in this manner the major portion of the atmosphere of a relatively small mold-space will be exhausted into a relatively great evacuated space and that thereafter the residual atmosphere of the mold (with such air, generated gases, and metallic vapors as may be present in the moltenv metal) will be exhausted into a second relatively great evacuated ICO ITO

space, and an extremely high vacuum will' be produced. The moltenmetal will bedelivered into the mold, however, before the piston in the pump P reaches the limit of its exhaust-stroke, and hence a substantially constant suction on the metal entering `the mold will be maintained by the plunger of the pump P through the pump-cylinder, the pipel, the piping 30,and the mold-passages leading to the mold-space, while communication between the pumpP and such mold is shut off, and not only will all of the gases and vapors present be drawnout of the moldspace and into the cylinder of thepump P', but the increase in the effective pressure on the molten metal entering the mold, which increase is due to the decreased resistance opposed by the almost perfect vacu um in the mold-space, will increase the condensing effect uponthe metal as the latter is rammed against the walls ofthe mold and into all the corners of the mold-space.

As soon as the molten stream strikes the walls of the metallic dies or plates 18 and 19, between which the moldspace is formed, the molten metal will begin to chill, and this chilling action is intended tobe hastened and the crystallization of the metal correspondingly checked by subjecting the mold to the action of a cooling medium, `a stream or streams of cold water being preferably circulated con-` tinuously in contact with the dies orplates 18 and 19. Here water istalen from a suit` able supply-pipe, such as 40, and is delivered through the branches of a Y in some suitable manner, as by a pair of tubes 41 and 511', to channels in the mold-sections o ando'. Here the mold-sections have projecting nipples to' receive the `ends of the tubes 41'and el', and these nipples have passages therein commu: nicating in this case with annular passages 21 and 21' in the mold-sections, these pas-` sages in turn communicating` withH corref` sponding outlet-openings through which the Water after circulating inmcontact with the dies 18 and 19 may be carried olf, as by a fun-` nel 22, having a waste-pipe 22', leading theref` prevention of shrinkage of the casting.

from. The vflow of water through the supply-J` pipe 40 may be controlled by a valve, such 186 and 86") and the valve c, aswell as the supas 42. It will be evident that as a stream of cold water will be constantly circulatedin; contact with each of the mold-sections the mold willbe keptpcool, and the molten metal delivered thereinto will be chilled and solidif` fied very quickly after entering the mold` space. -Itwill therefore be practically im pos-,1 sible for the. metal in cooling to form` large crystals and the resultant solid casting will have a very close graimand, moreover, the fine crystalline structure thereof will be uni-1 form throughout. y y 1 In order to force the particles of the cast-` ing into the most intimate relation `With one another, and thereby secure a castingA of maximum density, I mayalso exert upon the metal in the mold after the latter has been filled and either during cooling or after the metal has subsantially completely solidified a compressing force separat-e and distinct from that which is used to force the metal into the mold and into` the corners thereof. This additional compressing force may be applied at any time after partial cooling and before the metal after solidifyinghas become cold, and when applied while the cast-ing is hot and yet has completely solidified will resultin forging the casting into shape and converting the productfrom one having only the characteristics of cast metal into a casting having an extremely close grain and a structure less crystalline in character, the metal displaying in structure andcharacteristics the qualities possessed by wrought metal. This compressing force may be eX- erted in any suitable manner; but I prefer to make use of the valve o fort-his purpose. Here this valve has a cylindricalforward end which when the valve is completely closedthat is, when the forward or outer end thereof is in the plane of the meeting faces of the mold O and the nipple 12-will fill 4the outer cylindrical portion of the passage 10, but will not fill the tapering portion 10 of such passage during the early stages of the closing movement of this valve. I-Ience it will be to shut off the flow of molten metal into the mold it will n ot close communication between the valve-chamber and the mold-space untilit reaches the forward end of the tapered portion 10' of the passage 10, and that when it does reach this point the small body of metal in the cylindrical portion of theopening 10 will be forced forward bodily and willrbe added to the metal in the completely-filled mold-space,

theresult beingthat the metal in the mold will be condensed into a smaller bulk, owing to the addition theretoof this small bodyof metal in the forward cylindrical portion of the passage 10, the met-al so forced `into the mold-space by this additional compressing action being sufficient to effect the condensation of the largest quantity of metal into the smallest possible bulk and `lathe consequent The pu inps l? and P"`(inclu`ding the valves ply of water to cool the mold, may `becon- 1trolled by hand; but I` prefer toactuate the valver, the pump-pistons, and the valves 86 `and 86 mechanically-as, for example, from a shaft 2 by camsand springs in the manner shown herein. i Inthis casethe plunger@ is loperated from the shaft 2 by means of fa cam, `such as 50,having asingle cam-rim projectling therefrom, on the inside of which riman antifriction-roll, such as 5l', may travel, this roll in the present case being carried `by a lever 51, pivoted at 52 to a fixed point and having its freeA end pi-voted in turn to a connect ingfrod, such as 53, theupper end of `which lis `secured to a lever 54, pivoted between its ,ends on the upper side of the melting-pot and connected in turn at its free endto the plunevident that when the valve begins to move ICO IIO

ger p. A spring, such as 5l", may be employed to force the plunger down at the proper time, while the cam-ri n1 50 will serve to raise the plunger. Y

The valve 'u may be operated by a cam 55, secured to the shaft 2, and having a camgroove 55', in which may travel an antifriction-roll 56', secured to a lever 56, pivoted at one end at a ixedpoint 52 on the framework and at its other end to a connecting-rod 57, secured at its upper end to the long arm 35 of an angle-lever of which the rock-arm 35/ may form the short arm, this angle-lever he ing secured to a rock-shaft, such as 35. The cam-groove 55' is so shaped as to permit a quick movement of the valve 'u in either direction.

The piston 8O of the pump P will be operated by a cam, such as 60, also secured to the shaft 2 and having a cam-groove 60', in which may travel an antifriction-roll 61, secured to a lever 61, also pivoted at one end at a fixed point on the framework and pivoted at its other end to a link 62, connectedto the lower end of the piston-rod 8l. In a substantially similar manner the piston 80' of the pump P' may be controlled in its movements by a cam 65, having a cam-groove 65, in which may work an antifriction-roll 66', carried by a lever 66, pivoted at one end at a fixed point on the frame and at its other end to a link 67, connected to the piston-rod 8l.

The valve S6 may be operated from the shaft 2 by means of a cam, such as 70, which may coact with an antifriction-roll 7l', carried by a lever 71, pivoted at one end to a fixed support and pivoted between its ends to a connectingrod,such as 72,the upperend of which is pivoted in turn to a lever 73, supported on the pump P, and preferably forked at its end to engage an enlarged portion or projection on the stem of the valve 86, a suitable spring, such as 87, normally tending to hold. said valve closed. The valve 86 may be operated in substantially the same manner from the shaft 2 by means of a cam, such as 75, coacting with an antifriction-roll 76 on alever 76, pivoted at a fixed point on the framework,

and also having pivoted thereto between it@V ends a connecting-rod 77, the upper end' of which is pivoted to a lever 78 onV the pump P, this lever operating the valve 86 in substantially the same way that the lever 73 operates the valve 8G, and a spring 87' normally tending to hold the valve 86' closed.

It being understood that the valve c' isv closed and that the mold is in a position to receive molten metal to form a casting, the shaft 2 may be rotated either by hand or power in the direction of the arrow, as seen in Fig. l, whereupon the piston 80, ,which is not quite at a limit of its downward stroke, will be carried to its lowermost position by the cam 60, this position being indicated by the line a, Fig. 5, and immediately thereafter the valve 86, which during the descent of the plunger S0 is open in order to permit the partial exhaustion of the mold-space through the connections to the cylinder of ythe pump P, will be closed by the movement of the cam from b to c, Fig. 7, and communication between the cylinder and said pump and the mold-space will thus be shut olf completely, leaving in the mold-space only the residual atmosphere to be exhausted by the second pump P. Immediately after the valve 86 is closed by the cam 70 the valve 86 is opened by the cam moving from d to e, Fig. 8, and communication is established between the cylinder of the pump P and the moldspace. The cylinder of the pump P is preferably larger than that of the pump P, and the residual atmosphere of the mold-space may be exhausted into a space having the same cubic measure as the cylinder-space of the pump P before the piston S0' is at thelimit of its downward movement, and the remainder of the descent of the piston 80' may be utilized to maintain a constant suction upon the moldspace while the molten metal is being delivered thereinto. In the construction shown the cam 65 moves from the position shown at f, Fig. 6, and begins to draw down the piston 80', and at the same time (see linef, Fig. 3) the spring 5l begins to raise the lever 5l and force down the plunger 19. When the piston 80 has accomplished about two-thirds of its downward stroke (see line g, Fig. 6) and the plunger p about one-half of its movement in the same direction (see line g, Fig. 3) and the metal in the well 6, the passage 7, and the chamber 8 has developed the desired velocity, the cam 55 moves from position g to position h (see Fig. 4) and through its connections withdraws the rock-arm 35 quickly from the valve o and the pressure in the valve-chamber immediately shifts said valve, thus closing the passage 8 and opening that at l0. The plungerp and the piston 80 will continue to descend, the former exerting its pressure upon the molten metal to force the metal into the mold at one point and the latter maintaining a constant suction upon the mold-space at another point throughout the filling of the mold, the downward movement of the latter during this period being in this Icase about one-third of its stroke and the plunger reaching the limit of this movement somewhat in advance of the piston, as shown by linesj and l. (See Figs. 3 and 6.) About this time the cam 55 on the completion of the filling of the mold shifts the valve u again suddenly (see lines t' and 7c, Fig. 4) and closes the opening l0, thus cutting off the supply to the filled mold and at the same time compressing the small body of metal in the cylindrical portion of the passage lO into the mold-space. After the valve o has closed the cams 60 and 65 move from the position shown at Z and begin to raise the pistons 8O and 80 and at the same ,time the valve 86 is closed by its cam 75 (see lines Z and m, Fig. 8) for shutting off communication between the cylinder of the pump P/ and the mold-space.

IOO

IIO

During the ascent of these pistons or before they begin to descend again the mold should be lowered, withdrawn from the dischargenozzle l2, opened, .and the casting removed,

after which the mold may be raised again,

i the mold is in its Working position again and the pistons are at the limit of their upward movements (seelinen, Figs. and (i) the camrim 50' (see line n, Fig. 3) may begin to raise the plun ger p, and after the latter has reached the limit of its upward movement (see line r, ,Fig 3) the cam IO (see lines s and t, Fig. 7)

lnay operate to iopen the valve 86 again, whereupon the cam 60 will begin to carry down the plunger 80 (see line t, Fig. 5) to effect the partial exhaustion of the air from the moldspace and from the communicating passages in the piping, and when this plunger 8O reaches the position shown in Figi the parts will be in position to go through a new cycle of operations. i

Having described my invention, I claiml. Thatimprovementin the art of making a casting which consists in projecting the molten metal into and against the walls of the mold by a ram-like action produced by tirst setting in motion `a body of molten metal in a direction other than into the mold, and afterward, subsequent to the establishment of such flow, instantly diverting the direction of flow of the entire body of moving metal into the mold, whereby the kinetic energy of the entire mass of moving metal becomes effective to increase the impact of the entering metal.

2. Thatimprovement in the art of making a casting, which consists in first exhausting the mold and in then projecting the molten metal into and against the walls of the exhausted mold by a ram-like action produced by first setting in motion a body of molten metal in a direction other than into the mold,and then, subsequent to the establishment of such iiow, instantlydiverting the direction of flow of the entire body of moving metal into the mold, whereby the kinetic energy of the entire mass of moving metal becomes edective to increase the impact of the entering metal.

3. Thatimprovement in the art of making a casting which consists in projecting the molten metal into and against thewalls of the` mold bya ram-like action produced by maintaining a closing pressure upon the valve which controls the ejection of themolten metal and during this time establishing a movement in a body thereof in a direction other than into the mold, and afterward, subsequent to the establishment of such flow, suddenly releasing the pressure on the valve,

thereby permitting the instantaneous diver` sion of the direction ofow of the entire body f of moving metal into the mold, and in coni tinuing the application of the force by which such movement in the body ofmetal is accont-` plished during the open position of the valve. i i.

4. That improvement in the art of makinga casting which consists in project-ing the molten metal into and against thewalls of the mold bya rain-like action produced by maintaining a closing pressure upon the valve -which controls the ejection of the molten metal and during this `time establishing a movement in a body thereof in a direction other than into the mold, and afterward, subsequent to the establishment ofsuchtlow,

A and in cooling the castingduring the setting i of the metal.

5. Thatimprovement in the art of making a casting which consistsinprojecting the molten metal into and against the walls of the mold bya ram-like action produced by maintaining a closing pressure upon the valve which controls the ejection of the molten metal and during this time establishing a movement in a body thereof in a direction other than into the mold, and afterward, subsequent to the establishment of such iiow,

IOO

suddenly releasing the pressure on the valve,\ i

thereby permitting the instantaneous diversion of the direction of iiow of the entire body i of moving metal into the mold, and in continuingthe application of the force by which such movement in the body of metal is accomplished, during the openposition of the valve, and also continuing the pressure on the casting and cooling the same during the setting of the metal. 1 i

IIO

6. That improvement in the art of making a casting which consists in operating the pistons of air-pumps communicating with the mold and opening the valve in the passage-.way

leading from one pump to the mold, in then closing this valve and opening thevalvein the passage-way leading from another airpump to the mold, in projectingithe molten metal into and against .the walls of the eX- hausted mold `by a ram-like action produced by iirst setting in motion a body of molten metal in a direction other thaninto the mold, and maintaining a pressure during this operation -on the valve controlling theinjection of molten metal, and finally, after said secondi mentioned valve in the passage-wayleading to the second pump has been opened, suddenly releasing the pressure on saidmetalcontrolling valve, thereby permitting the instantaneous diversion of the direction `of iiow of the entire body of moving metal into the `mold.

7. That improvement in the art of making a casting, which consists in first exhausting the mold, in then projecting the molten metal into and against the walls of the exhausted mold by a ram-like action produced by first setting in motion a body of molten metal in a direction other than into the mold, and after the mold is exhausted and such ow inaugurated, instantly diverting the direction of flow of the entire body of moving metal into the mold, and in cooling the casting during the setting of the metal.

8. That improvement in the art of making a casting which consists in operating the pistons of air-pumps communicating with the mold and opening the valve in the passage-Way leading from one pump to the mold, and then closing this valve and opening the valve in the passage-Way leading from another airpump to the mold and in projecting the inolten metal into and against the Walls of the exhausted mold bya ram-like action prod uced by iirst setting in motion a body of molten metal in a direction other than into the mold and during this operation maintaining a pressure on the Valve controlling the injection of molten metal and then suddenly releasing the pressure on said metal-controlling valve after the second-mentioned valve in the passage- Way leading to the second pump has been opened, thereby permitting the instantaneous diversion of the direction of iioW of the entire body of moving metal into the mold and in continuing the application of the force Which sets said body ot' molten metal in motion after said metal-controlling Valve has been opened.

9. Thatimprovement in the art of makinga casting which consists in operating the pistons of air-pumps communicating with the mold and opening the valve in the passage-Way leading from one pump to the mold, in then closing this valve and opening the valve in the passage-Way leading from another airpump in the mold, in setting in motion a body of molten metal in a direction other than into the mold, in maintaining a pressure on the valve con trolling the injection of molten metal during this operation, in suddenly releasing the pressure on said metal-controlling Valve after the second-mentioned valve in the passage-Way leading to the second pump has been opened, thereby permitting the instantaneous diversion of the direction of iiow of the entire body of moving metal into the mold, and in continuing a pressureon the casting during the setting of the metal.

l0. That improvement in the art of making a casting, Which consists in first exhausting the mold, in then projecting the molten metal into and against the Walls of the exhausted mold by a ram-like action produced by establishing a movement in a body ot' molten metal in a direction other than into the mold, and then, after the mold is exhausted and such flow is inaugurated, instantly diverting the direction of flow ofthe entire body of moving metal into the mold, and in cooling the casting and maintaining a pressure thereon during the setting of the metal.

CURTIS H. VERDER.

Witnesses:

E. BARBIE SMITH, HENRY BIssELL. 

